Moving the girls into coop soon

Hi all,

We are planning to move our young hens into their outdoor coop and run soon. As we are still many weeks away from laying eggs I was thinking of shutting off the nestbox which is bolted to the end of the indoor perching/sleeping area until they are nearing egg laying age.
My thinking is that this will encourage them to sleep on the perchs provided in the coop rather than sleep and poo in the nest box which i hope to keep cleaner for them to lay when ready.

Does this sound like it might work or will they sort themselves out?

thanks in advance

Nige